SET DEADLOCK_PRIORITY

SET DEADLOCK_PRIORITY - is exactly what it sounds like: Specifies the relative importance that the current session continue processing if it is deadlocked with another session.

SET DEADLOCK_PRIORITY { LOW | NORMAL | HIGH | <numeric-priority> | @deadlock_var | @deadlock_intvar }

<numeric-priority> ::= { -10 | -9 | -8 | … | 0 | … | 8 | 9 | 10 }
LOW maps to -5, NORMAL to 0, and HIGH to 5.

http://technet.microsoft.com/en-us/library/ms186736.aspx