[JURIST] The US Senate [official website] is expected to vote Wednesday on whether to allow oil drilling in the Arctic National Wildlife Refuge (ANWR) [official website]. Sen. Ted Stevens (R-AK) [official website] has added the measure to the 2006 military spending bill [bill summary], though Democrats have threatened to filibuster the bill because the ANWR provision is unrelated to military spending and violates Senate rules. Stevens has been working since the 1980s to open ANWR to drilling; supporters of the measure say that opening the refuge is critical to stopping a decline in US crude-oil production, but opponents say that the land and its wildlife must be protected. Wednesday's vote is expected to be tight, and it's unclear whether the ANWR provision will be removed from the spending bill if Democrats are able to successfully filibuster it. Democrats have also indicated that they will seek a parliamentary ruling that the ANWR amendment is not relevant to the bill. The US House approved the spending bill [JURIST report] on Monday. Reuters has more.