In a letter directed to the executive Board of UAW Local 2865, the California Teamsters have reiterated their opposition to BDS, stating unequivocally that they “cannot conceive of an action more hostile to the interests of [Teamsters] members and more antithetical to the most basic principles of the union movement”

The letter is reproduced in its entirety at the website of Informed Grads, a group organized in opposition to the Dec. 4th BDS resolution at the University of California

Dear [Michelle] Glowa and Members of the Executive Board,

It has come to our attention that the Executive Board of UAW Local 2865 has endorsed the “Global Boycott, Divestment, and Sanction Movement” against companies that do business in Israel. In addition, we understand you have also endorsed the so-called “Academic and Cultural Boycott of Israel.” We further understand that you are putting the matter to a vote of your bargaining unit members on December 6 [sic], 2014.

Teamsters Joint Council 7 and 42 is comprised of our members in California, Nevada, Hawaii, and the Pacific. This includes Local 2010 that represents 14,000 employees throughout the University of California system.

As you are no doubt aware, the companies that are targeted by the BDS movement include numerous employers that are represented by organized labor, including many thousands who are represented by the Teamsters. Indeed, some of the companies you wish your union to boycott and divest from are represented by the United Auto Workers. In the case of the Teamsters, we represent tens of thousands of employees at the following companies that are listed as targets of the BDS campaign:
Boeing
Cemex
General Dynamics
General Electric
ITT
Lockheed-Martin
Northrup-Grumman
Whatever your motives, we cannot conceive of an action more hostile to the interests of our members and more antithetical to the most basic principles of the union movement than for a union to call for actions which are intended to do harm to the economic security of other union members. We would find it difficult to ask our members to support your union in a labor dispute with the University of California so long as you are engaged in activities that are fundamentally hostile to their interests.

Giving you the benefit of the doubt, we can only assume that you took your actions without consideration of the potential harm to hard working union members across California and the United States. We ask you to look at that issue now. Unlike the members of your union, who are graduate students and therefore union members for a short period of time, our members are working in jobs that must support them for a lifetime and it is our job to protect them for all of their working lives.

We would strongly request that you reconsider your actions.

What's happening is a conflict between different unions - the UAW graduate student union, who support BDS, and the Teamsters, who oppose it.

From the press release, linked:
"UAW 2865, a labor union representing over 13,000 teaching assistants, tutors, and other student-workers at the University of California, has become the first major U.S. labor union to hold a membership vote responding to the Palestinian civil society call for boycott, divestment and sanctions against Israeli occupation and in solidarity with Palestinian self-determination. The vote passed, with 65% (almost 2/3) of voting members in support. Over 2100 members voted, a testament to union democracy.

"The measure calls on
1) the University of California to divest from companies involved in Israeli occupation and apartheid;
2) the UAW International to divest from these same entities;
3) the US government to end military aid to Israel.
4) 53 % of voting members also pledged not to “take part in any research, conferences, events, exchange programs, or other activities that are sponsored by Israeli universities complicit in the occupation of Palestine and the settler-colonial policies of the state of Israel” until such time as these universities take steps to end complicity with dispossession, occupation, and apartheid.
- See more at: http://mondoweiss.net/2014/12/workers-becomes-endorse#sthash.ig3Fqcw6.dpuf";

Despite the Teamsters letter, the membership voted to support BDS.

Additional conflict is likely because organized labor has other unions that organize at military-industrial-congressional complex companies. This is not unusual - these memberships represent numerous jobs.

That said, it's not known if divestment in these companies would necessarily lead to job losses. These companies are primarily government contractors, and it's Congress that influences whether the number of jobs expands or contracts. For example, locally, the sunsetting of the C17 transport plane led to the contraction of the workforce at Boeing in Long Beach. When the government buys less, the production is cut, and people are laid off. Investor money probably helps more in funding expenses like R&D labor (scientists, engineers, etc.), which aren't as well represented by labor unions.

This type of intra-labor conflict is one of the reasons why boycotts focus on companies hostile to labor unions, or with low rates of union membership, like Caterpillar and Hewlett Packard. The fact that they achieved this general level of support is significant.

A group within labor likely to oppose this action are the Jewish Labor Committee. Another group within labor likely to support BDS include US Labor Against War.

http://www.jewishlaborcommittee.org/2014/12/on_the_vote_of_university_of_c.html

http://uslaboragainstwar.org/Articles/index?tag=BDS&tag_id=4646

At the SF ports, BDS stopped access to the ports, and the ILWU didn't cross the community picket. While this isn't an endorsement, and the statements around it have a negative cast because they refer to risks to safety, it's really a way to show solidarity by honoring the picket line.

There is a website of labor union folks who support Palestine:
http://laborforpalestine.net/

For the most part, the union locals don't take a position on BDS or Palestine. This is in line with the general trend of not taking positions on international issues, and generally aligning with whatever the state department, by default.

The voter turn-out was extremely low- only 2,000 of the eligible students (Over 50,000) voted for this, essentially hijacking the union.