By Rachel More

BERLIN, March 4 (Reuters) – Germany’s top industrial union is fighting for more influence at Tesla‘s gigafactory outside ‌Berlin, where staff are voting for a new works ‌council after a campaign marked by mud-slinging and legal challenges.

Voting began on Monday ​at Tesla’s Gruenheide plant, the U.S. electric car maker’s only European production site, with results expected later Wednesday.

The current council is dominated by non-union members. The IG Metall union is fielding 116 candidates ‌in a bid ⁠to win a simple majority – 19 of 37 seats. The union secured 16 in the last election ⁠two years ago, when the council had 39 seats.

IG Metall has accused management of stoking anti-union sentiment. Plant director Andre Thierig has ​countered that ​the union is focused solely ​on boosting IG Metall membership.

“We ‌are very satisfied with our election campaign. We are running with a great team and our issues are clearly striking a chord with our colleagues,” IG Metall’s lead candidate Laura Arndt said in a statement to Reuters.

Works councils, elected by staff, are ‌a cornerstone of German labour relations, ​representing employees in talks with management.

IG Metall ​dominates councils across German ​carmakers – including Volkswagen, BMW and Mercedes – but remains ‌the underdog at Tesla, whose CEO ​Elon Musk is ​outspoken in his criticism of unions.

Tensions peaked in February when Tesla accused an IG Metall trade unionist of secretly ​filming a works ‌council meeting and filed a criminal complaint.

IG Metall dismissed the ​allegation as a “calculated lie”.

(Reporting by Rachel More and Christina ​Amann. Editing by Mark Potter)